1. Field of the Invention
The present invention relates to a system and method for signaling a remote location. More particularly, the invention relates to a system and method for sending a signal to a remote location, such as a vehicle or building, over a wireless network in order to control a device located at the remote location.
2. Description of Related Art
Car-jackings and vehicle theft have become a serious problem, especially in the past few years. Many vehicle theft prevention systems for automobiles, trucks, and boats are known and presently used. These systems fall into three general classes: physical locking devices, alarm systems, and systems for disabling the vehicle. Nevertheless, vehicle thieves and car-jackers have conducted a running, and mainly winning, battle with such theft prevention systems.
Physical locking devices constitute the first class of vehicle theft prevention systems. An example of such a device is The Club.RTM., which includes a metallic shaft and a locking mechanism located on the shaft. The Club.RTM. attaches to the steering wheel of a car or truck and, while attached, inhibits movement of the steering wheel. Thieves, however, can easily defeat The Club.RTM. and other physical locking devices, for example, by simply spraying freon into the locking mechanism and striking the lock with sufficient force to break it. The physical locking device can then be easily removed from the steering wheel.
Falling within the second class, myriad alarm systems exist for preventing vehicle theft. Such systems operate to deter a thief before the thief undertakes to steal a vehicle. Alarm systems employ various deterrence methods, including sound and visual alarms. Nevertheless, thieves can easily disable alarm systems, thereby rendering them ineffective, even useless in some cases. Even if not disabled, a thief can allow the alarm to activate and simply drive away in the vehicle while the alarm is sounding. Thus, alarm systems cannot counteract a determined thief.
As to the third type, various systems exist for disabling a vehicle. For example, some systems work in conjunction with law-enforcement agencies, by which an agency can remotely disable the vehicle. Such systems, therefore, require intervention by the agency and thus cannot be implemented by the vehicle owner without some assistance. In a similar system, the vehicle owner must call a central service, which can then transmit a signal over a satellite network to the vehicle. This system, however, only provides the capability to track the vehicle, but not to a shut it down. requires the central service and thus can be costly and can incur delays between the owner's initial call and the transmission of a cut-off signal to the vehicle by the service. In addition, the law-enforcement and central service systems require the vehicle owner to invest in expensive electronic components for installation in the vehicle and only work in a covered "local" area.
Other vehicle disabling systems use infra-red carrier waves produced by a transmitter that must be directed towards a receiver in the stolen vehicle to terminate the vehicle's operation. Such systems, however, require a short distance and a direct line of sight between the transmitter and receiver. Similar systems employ radio transmission devices to disable the vehicle. These systems also suffer from a limited range, and have the disadvantage of disabling all vehicles equipped with a similar radio receiver. Moreover, the infra-red and radio systems are expensive and demand that the vehicle owner invest in costly, customized devices for the vehicle.
Still other vehicle disabling systems use cellular telephone systems to disable the vehicle. In these systems, a cellular telephone, installed in the vehicle, receives signals sent over a cellular network by a caller. Such systems, however, have several drawbacks. First, they require an expensive, complicated cellular telephone in the vehicle that operates in full-duplex and receives voice signals. Second, because cellular systems receive and transmit relatively high power signals, the cellular telephone requires an antenna that is mounted on the exterior of the vehicle, making the antenna vulnerable to vandalism and thieves, who can disable the system by removing or damaging the antenna. Without an operational antenna, the cellular-based vehicle disabling system is rendered non-operational.
Finally, these systems, being cellular, have a limited geographic range of operation. The vehicle owner must subscribe to a cellular provider, which has only a limited geographic region in which it can provide service to its subscribers. Generally this is limited to a city, unless the provider interfaces with other cellular providers in other regions. The net effect is that, when a vehicle equipped with the cellular disabling system travels beyond the range of its cellular provider, the system is rendered useless. This is not the case, however, with satellite-based communication systems, such as pager systems.
Conventional vehicle disabling systems also lack the capacity to transmit signals back from the vehicle to the individual or entity that triggered the system. Such signals can be used to indicate the status of the vehicle, such as whether it has been disabled and where it is located. The benefit of transmissions back from the system is clear, providing the vehicle owner with important information for personal use and that can be relayed to law enforcement agencies.
Even beyond the application of disabling or signaling a vehicle, it is highly beneficial to be able to remotely control various devices and systems located in buildings or structures. The ability to remotely control various devices and systems has a wide variety of applications. For example, wireless systems can be used to control air-conditioning, alarm, and lighting devices and systems. At present, however, no remotely operated system is available that combines low cost and simplicity with unlimited range of operation. Moreover, no system is available that permits communications, such as status reports, back from the remotely located devices and systems.
In light of the foregoing, a need exists for a system and method for communicating with a vehicle or other remote location using a wireless network and an inexpensive transceiver located within the remote location having a virtually unlimited range of operation.